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With budget cuts in the works for everyone these days, NASA has decided to float an alternate plan for returning to the moon that is just a little bit cheaper than the current proposal. Of course, the new option would be very reminiscent of the old Apollo space capsule instead of the tricked out shuttle currently planned. "Officially, the space agency is still on track with a 4-year-old plan to spend $35 billion to build new rockets and return astronauts to the moon in several years. However, a top NASA manager is floating a cut-rate alternative that costs around $6.6 billion. This cheaper option is not as powerful as NASA's current design with its fancy new rockets, the people-carrying Ares I and cargo-lifting Ares V. But the cut-rate plan would still get to the moon."

"It is a small effort, it hasn't been looked at across NASA, because we already have a plan: Constellation. I think we should fund the plan."

The point of Shannon's presentation was to say exactly what he says at the beginning of that video. NASA is *always* looking at *all* the options and the DIRECT people are just, simply, wrong; that's why no-one is interested in their shit. Not because there is some great big conspiracy to quash their option.. but because the mission requires a Saturn class or bigger vehicle. NASA has been given the mission to return astronauts to the surface of the Moon, use in-situ resources and stay there permanently.. then move on to Mars. You're not going to land an outpost on the Moon with a 70mt launcher, and you're definitely not going to go to Mars with that.

"NASA investigates other options and doesn't look at problem in blinkered and myopic way" - News at 11.

NASA always looks at these ideas and then normally decides that either the risk profile is too high (the most impressive thing about the first moon landings were the LACK of deaths) or that it just doesn't stack up as something that will deliver the overall objectives.

Hell in theory a great big Trebuchet could get someone to the moon, pretty one way mission though. The challenge here is to get someone to the moon, return them safely to earth and to establish a base on the moon. This is a HUGE challenge and one where a government agency has to do so at levels of safety that a commercial organisation wouldn't bother to meet.

When people bitch and moan about the price then that is fair enough, but please lets be honest here. Getting to the moon remains a HARD problem, the Chinese are going to take a long bunch of years to get there, and you can't solve hard problems with CostCo models. Either the aim is to go to the moon or not. The price comes from the aim and ambition not because NASA act like congress after pork.

James Michener, the writer, was also on the NASA advisory board, and in his fiction Space [wikipedia.org], there are a few pages on the conflict in the planning stage between the Earth orbit faction, in which the base module would orbit Earth and the lander would go to the Moon surface and back, and the Lunar orbit faction, whose design was more efficient and eventually won. One of the characters says that by doing that the US had foregone the availability of a space station. It is interesting that the fallback plan goes in that direction, because it could be relatively easy to have the cargo craft double as a lorry to the ISS.

We don't need another Apollo-like mission to the moon. We've already done those enough. It's just going to cost money without any substantial new information. The next mission to the moon should be bigger and a lot different from what we have done before. Either have the balls to commit yourselves and the money to something meaningful or don't do it at all. I'd also like to point out that the moon isn't going anywhere in the near future. If a meaningful mission would cost too much now, there's no shame in waiting for the technology to became more mature.

I think it would be quite sensible for them if they were studying alternative plans. Surely redundancy is simply sound engineering principle? It's something that the shuttle never had either, and look what happened the two times they had to be taken out of service.

Of course the new option would be very reminiscent of the old Apollo space capsule instead of the tricked out shuttle currently planned.

Methinks that even the author didn't RTFA... The shuttle-based plan is the new contingiency plan. And both plans would involve the same "Apollo-like" Orion capsules. I guess that if no one else does, then its misguided to even expect authors to RTFA?

The worrying part of this design is that the same orion capsule would be only able to carry 2 astronauts at a time during launch, presumably due to fuel constraints. While the rest of it sounds like a pretty reasonable bet, this bit just makes me think "well what's the point?"

Why people... Let's see. The ultimate goal of the program, as stated by Pres. Bush, is to put a man on Mars.

Using the most energetic path we have available, Mars is over 3 months away. Assuming the nuclear power plant is out, then the time to Mars is closer to 9 months with an ion/vasimr engine; or, 18 months coasting.

IF you're going to send people to Mars, it seems like a good idea to test your equipment and get some practical experience living in a little (Mars) or no (Moon) atmosphere, low gravity, high incident solar radiation environment with dust that can best be described using the word "evil". If you can help it, you want to do this as close to help as possible in case something goes wrong. The Moon is 3 days from Earth.

Now someone is about to post the comment whose premise is "The Moon is NOT Mars!" I'm aware of that. So is NASA. Mars has a toxic atmosphere (0.01% Earth pressure, primarily CO2). Mars has water vapor, condensation, and ice, all of which affect equipment and all of which the Moon lacks. Martian dust is not Lunar dust (you could argue Lunar dust is more evil). Martian gravity (1/3G) is higher than Lunar gravity (1/6G). There's still a lot of commonality, enough to gain valuable experience testing equipment and methodologies. It would not be much help to our astronauts if we send them to Mars with equipment that fails within hours, or send them with a survival plan that's unworkable. Especially if those problems could have been found with a little testing.

For what it's worth, I think we will get to Mars; but, it's going to be 30 to 50 years, not the 20-25 former Pres. Bush was arguing for.

While I agree it's a great acheivement to get people to the moon AND back, I think you're understating the challenge of hitting an object
382500 km away and moving at 3600 km/h relative to the earth. That's not a bet I'd like to take.

It's not a fuel constraint. This "new" Shuttle Derived Heavly Lift Vehicle plan is essentially the Shuttle C cargo-only design that they looked at a few decades back. They've stuck the manned Orion capsule and support module in the cargo container... It simply does not have the lift capacity to put something big enough into trans-lunar orbit. If they cut the crew back to two, and cut all the associated equipment requirements, it barely gets you there. Shuttle hardware was designed to be single stage to orbit. It was never intended to send men to the Moon.

It's so damn simple they can't see the forest for the trees. Ares 1 needs to be cut. It doesn't have the capacity. This was aparent some time ago and they should have looked for alternatives when they saw that. They need to replace it with an existing heavy lift vehicle and expend the effort to man-rate that vehicle. There are plenty of options, the best of which is probably Delta IV Heavy. If we use a common adapter, then the ESA Ariane and Japanese H2 become options with a little further development. In addition, Ares V development needs to continue so we have the cargo lift capacity to get the big stuff to orbit. Of course, this is just my opinion.

Aiming the thing would be the easy part; decelerating once in the moon's gravity well and in the right orientation not to kill everyone is a bit harder with a ballistic lander.

I think either the acceleration from the trebuchet or the subsequent burning up in the atmosphere on the way up would make decelerating into moon orbit a moot point.

Unless, of course, your trebuchet is several kilometers high and you can clear most of the atmosphere while being accelerated by the thing.

Hm. I wonder if we'll ever see an electro-magnetic launch system. It'd be a megaconstruction, but just think about the advantages like the efficiency of electromagnetic propulsion or the simple fact that the payload doesn't need to lug all the fuel around.

I understood this -- I guess I was just oversimplifying. I wouldn't want anyone to think you could simply compress the Martian atmosphere to breathable pressures and go -- that would, in fact, be toxic. I got the pressure wrong, by the way. It's ~0.01atm = ~1% Earth sea-level pressure = ~600 Pa = ~0.13 psia at Mars mean ground elevation. (Haven't had my coffee yet) Given that the absolute pressure on Mars is so low, you have a lot more to worry about than the CO2, if you know what I mean.

It'll take 5.5 years to man-rate a Delta IV, and you'll have to pay for the privilege and gift the ULA new launch facilities (http://www.youtube.com/watch?v=i2m-UoOM7eg). Alternately, you could fund COTS-D and have a manned vehicle from SpaceX in 2.5 years (http://www.youtube.com/watch?v=O81Zq02eStg). If you gifted SpaceX the launch escape system you can have a manned vehicle next year (I totally just made that up, but it makes sense to me). That said, if you cut Ares I now you're cutting Ares V. Ares I is "behind schedule" because they're working on the 5-segment solid stack. Without that the Ares V won't fly either.. so, sooner or later they have to do this work. Hopefully after the Ares I-X flight test (which, btw, will be a 4 segment solid stack, I know, wtf) people will stop armchair quarterbacking and just let NASA do their freakin' job.

Oh yeah, it also showed how completely ridiculous the idea of on-orbit assembly remains. I'd love it if it wasn't true. We could launch up parts, assemble them into some giant battlestar galactica type ship and fly around the solar system in style. But the reality is, just pulling some parts out and putting some new ones in took hours and hours of grueling labor. We really need better suits, with better gloves, and the Moon shot will motivate that.

Yes, life support is an issue, but we now have almost 40 years of experience in operating space platforms and I reckon the state of the art has advanced enough to consider a very long mission.

Energy supply is the biggest problem out around Saturn so we would have to lose our phobia about operating fission reactors in space. Ion drives have very high specific impulse. With enough power it should be able to push a manned spacecraft. I also think we should look into building a hybrid fission/ion drive. In theory you could go:

Fission -> electricity -> ion propulsion

But since a lot of the energy in an ion drive is used to ionise the reaction mass, and since fission reactors are so good at ionising things I suggest we look at directly ionising xenon with gamma rays.

Anyway I think it is worth doing. Imagine how hard the lunar flight must have seemed in 1960.

Bingo. The ultimate goal should be a colony that is capable of growing without further input of matter or energy from earth. In the interim a base would be necessary to sort out the bugs and get proof of concept. There are probably many other things that can generate the know-how on earth for a fraction of the price.

The Americans have already been to the moon. I find it sad that they managed to do the entire Apollo program [wikipedia.org] for somewhere between 20 and 25 million (135 billion in 2005 dollars), when they had to develop completely new technology. Why can't they just rebuild the Apollo rockets. Did they lose the plans along with the moon landing tapes? Going to the moon should have been figured out by now. We don't need any new technologies to accomplish this. Just reuse old designs.

It'll take 5.5 years to man-rate a Delta IV, and you'll have to pay for the privilege and gift the ULA new launch facilities (http://www.youtube.com/watch?v=i2m-UoOM7eg).

5.5 years and paying for the priveledge... Apply that to SpaceX please and tell me how that affects your suggestion. You pay for the priveledge anyway. NASA does not build it's own launch vehicles. Even the shuttle, which is a NASA design, was built and is maintained by an army of contractors. Engines are supplied by Pratt-Whitney Rocketdyne. Boosters by ATK. Tanks by Lockheed-Martin. and so on. For what it's worth, it probably won't take 5.5 years to man-rate a Delta IV. That, in their own words, is a conservative estimate. It could certainly happen faster. It, honestly, could take longer. Yes, ULA launch facilities are inadequate for manned vehicle launch. Existing shuttle facilities won't work for Ares I or Ares V either. Either way, you have to upgrade the facilities you have.

Alternately, you could fund COTS-D and have a manned vehicle from SpaceX in 2.5 years (http://www.youtube.com/watch?v=O81Zq02eStg). If you gifted SpaceX the launch escape system you can have a manned vehicle next year (I totally just made that up, but it makes sense to me).

SpaceX is clearly well on there way. They have, however, set extremely optimistic schedules and have not done significant work to man-rate the platform or the Dragon module. I fully expect them to be performing their COTS ISS supply mission in the next year or two but I don't put as much faith into their ability to scale up to putting people into LEO as quickly as they say they can. That issue was brought up during the Augustine Commission hearing. Gifting the launch escape system to SpaceX won't work -- it's designed for Orion, not Dragon. It would need to be redesigned for use there. Oh, btw, don't take me to task and then use "just made that up" in your reply

That said, if you cut Ares I now you're cutting Ares V. Ares I is "behind schedule" because they're working on the 5-segment solid stack. Without that the Ares V won't fly either.. so, sooner or later they have to do this work

Ares 1 isn't behind because of the 5-segment stack. It's been ground tested. It works. It's behind because there are vibration issues requiring redesign of the 5-segment stack and interstage. These vibration issues are present in the 4-segment stack as well but are damped by the mass of the shuttle system. These changes are specifically required for the Ares I use and would not affect Ares 5, which I'll get back to... There are also limitations on mass, which have required additional engineering on the Orion and a cut in the number of people carried to LEO. A single booster, while it generates a lot of thrust, has insufficient capability to carry a heavy manned vehicle to LEO. I'm aware that the current Ares V design requires the booster; and, that cutting Ares 1 development moves some of the booster development cost to Ares V. For what it's worth, this applies to your previous suggestion to use SpaceX COTS capability as well. I'm suggesting that using the booster in the Ares I configuration to launch people to LEO is a poor plan. The only big issue here is, what happens if the manufacture of the SSRB's is shut down for a while.

Energy supply is the biggest problem out around Saturn so we would have to lose our phobia about operating fission reactors in space. Ion drives have very high specific impulse. With enough power it should be able to push a manned spacecraft. I also think we should look into building a hybrid fission/ion drive. In theory you could go:

The problem here is shielding. If you stick a fission reactor on an unmanned craft, you can get away with much less shielding than if you stick it on a manned craft. And with more shielding comes more weight.

I would use the classic Discovery 1 configuration. Put the reactors and engines out on a truss. The primary radiation shield only has to stop radiation which would reach the hab module. Secondary shielding would be the water stored in the walls of the hab module. But I agree that shielding would be a real challenge.

Obsolescence. Many of the parts used in those old designs are no longer available, and it would cost far more to try and get those production lines spooled up (probably 3/4 of the production lines used to make electronic components for the old Apollo series computers are now EPA Superfund sites...) than to create a completely new design.

> Redundancy in engineering is NOT proceeding on two similar projects at the same time.

This isn't engineering, this is aerospace. In this case they almost always build two designs and select one. For instance, the F-35 was selected from the X-32 and X-35.

In every other case I can think of, at least two designs are presented and one goes to metal. For Apollo, Nova and Saturn were both serious contenders, and the final decision was based on factory capacity, not technical issues. In the case of the Shuttle, North American and McD designs both went right up to the final decision, and Grumman was kicked out only in the late stages.

This all-eggs-in-one-basket approach is actually highly unusual for the aerospace industry, at least in terms of government funded projects. Consider that they funded both Delta and Atlas, precisely to ward off ending up with nothing if the one they selected came in too heavy - precisely what's happening with Constellation.

Hubble was never meant to be serviced in space, that's why it was such a pain in the rear to do so.

But of course it was. The first service mission was planned even before HST launched. The schedule got mixed up
a bit because of the corrective optics that needed to be made, but manned service missions were part of the
design from the beginning. That's one of the reasons why HST's orbit is where it is: As far out as possible
within the constraints of "can still be reached by the Shuttle".

However, some of the things that got fixed/swapped/serviced on this year's mission were indeed not intended
for in-orbit maintenance.

According to Aldrin and others, the general concensus was the first landing's chances were 50:50.

Re-reading the recent influx of 40th annivesary articles about the Appollo program, on every level the success of the moon landings seems absolutely incredible. The more I read, the more my mind boggles at how touch-and-go the whole escapade was. Just watching the LLRV test flights [youtube.com] makes me wonder what the hell was going through their minds at a time when they didn't even know what the surface of the moon was made of.

The more you investigate this subject, the more you realise that modern technology doesn't contribute that much to this gargantuan task. It's just brains, ideas and some sort of test-pilot 6th sense.